diff --git a/libraries/AP_GPS/AP_GPS_SIRF.h b/libraries/AP_GPS/AP_GPS_SIRF.h
index c69176a02d..15d1ece9bf 100644
--- a/libraries/AP_GPS/AP_GPS_SIRF.h
+++ b/libraries/AP_GPS/AP_GPS_SIRF.h
@@ -25,7 +25,7 @@
 #include <AP_Common.h>
 #include <AP_GPS.h>
 
-#define SIRF_SET_BINARY "$PSRF100,0,38400,8,1,0*3C"
+#define SIRF_SET_BINARY "$PSRF100,0,38400,8,1,0*3C\r\n"
 
 class AP_GPS_SIRF : public AP_GPS_Backend {
 public: